This disclosure relates to a steam pressure regulator, and more particularly, to a steam pressure regulator for use in a fuel cell system.
It is believed that a fuel cell includes two electrodes sandwiched around an electrolyte. It is believed that oxygen, e.g., from air, passes over one electrode and hydrogen, e.g., from a hydrogen source, passes over the other electrode, and in a chemical reaction, generates electricity.
It is also believed that the hydrogen source can be a reformer that produces hydrogen gas as one product of another chemical reaction. It is believed that one type of reformer uses steam, oxygen, and gasoline to produce hydrogen, carbon dioxide, and carbon monoxide. Thus, it is believed that there is a need to regulate the steam pressure supplied to a reformer in a fuel cell system.
The present invention provides a steam pressure regulator for a reformer of a fuel cell system. The reformer includes an inlet in fluid communication with a steam source, and an outlet that provides a supply of hydrogen gas. The steam pressure regulator including a valve body, a valve movable between first and second positions, and an actuator. The valve body defines an internal flow passage between first and second ports. The first port is adapted to be in fluid communication with the inlet of the reformer. The first position of the valve substantially prevents fluid communication through the internal flow passage, and the second position of the valve permits generally unrestricted fluid communication through the internal flow passage. The actuator includes an actuator body that defines a chamber, a movable actuator wall that divides the chamber into first and second chamber spaces, and a shaft that couples the movable actuator wall to the valve. The shaft includes a signal passage that provides fluid communication between the first port and the first chamber space, such that fluid pressure at the first port is communicated through the signal passage to the first chamber space.